Hem-folding and shaping device for sewing machines



' Dec. 8, 1936. v J, E, ACKERMAN 2,063,833

HEM FOLDING AND SHAPING DEVICE FOR SEWING MACHINES Filed March 2, 1935 3 Sheets-Sheet 1 3mm pig/mes EH0 lierman Wflweaa:

Dec. 8, 1936. J. E. ACKERMAN HEM FOLDING AND SHAPING DEVICE FOR SEWING MACHINES 3 Sheets-Sheet 2 Filed March 2, 19:55

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Dec. 8, 1936. R N 2,063,833

HEM FOLDING AND SHAPING DEVICE FOR SEWING MACHINES Filed March 2, 1935 3 Sheets-Sheet 3 MQJQWQ MW cloth-plate partly in section.

Patented Dec. 8, 1936 UNITED STATES AET OFFIE HEM-FOLDING AND SHAPING DEVICE FOR SEWING MACHINES Application March 2, 1935, Serial No. 9,010

6 filaims.

This invention relates to improvements in work-folding and guiding devices for sewing machines and has for its object to provide means for producing a hem of uniform width in a body material, and particularly in body materials having heavy cross-seams.

The invention consists in the work-folding, guiding and feeding devices as hereinafter described and pointed out in the appended claims.

In the accompanying drawings, Fig. 1 is a front side elevation, partly in vertical section, of a portion of a sewing machine having the present improvements applied thereto. Fig. 2 is a front end elevation of the sewing machine, with the Fig. 3 is a top plan view of a portion of the cloth-plate of the sewing machine and of the attachment applied thereto, the presserand feed-bars being shown in horizontal section. Fig. 4 represents a perspective view of the shaping member for the inner fold-edge of the hem. Fig. 5 represents a sectional view of the hem-shaping elements, taken substantially on the line 5-5 of Fig. 3. Fig. 6 represents a section similar to Fig. 5, but taken on the line 66 of Fig. 3. Fig. 7 represents a perspective view of the hemmer.

Referring to the drawings, a commercially well known sewing machine, to which the present improvements have been applied, has a frame including a bed-plate l and a hollow bracket-arm 2 terminating in a head 3 overhanging the bedplate, said bed-plate serving as a work-support or cloth-plate.

Rotatably journaled in suitable bearings in the bracket-arm 2 is a main or needle-reciprocating shaft 4 operatively connected by a link 5 to a vertically reciprocatory needle-bar 6, carrying at its lower end a needle 1. The needle-bar 6 is journaled for endwise reciprocation in suitable bearings provided in a vibratory frame 8 hung upon a fulcrum-pin 9 for vibratory workfeeding movements about an axis substantially parallel to the axis of rotation of the main shaft 4. The needle-bar frame 8 derives its vibratory movements from a crank-arm H! of a rock-shaft ll journaled in the bracket-arm 2 below and in parallel relation with the main shaft 5, said rock-shaft l I being actuated in the usual or any suitable manner.

Suitably secured upon the bed-plate l is a throat-plate l2 having a feed-slot 13 through which operates a lower feed-dog l4 having a needle-aperture l5, said feed-dog being actuated in the usual or any suitable manner to advance the work in timed relation with the work-feeding movements of the laterally vibrated needle 1.

Opposed to the lower feed-dog I4 is an upper feeding foot iii, preferably having a serrated work-engaging face and provided with a needle- 5 aperture ii. The shank of the feeding foot I6 is secured upon the lower end of a feed-bar l8 journaled for vertically reciprocatory movements in a suitable bearing aperture provided in the vibratory frame 8. bar i8 is connected by a link 19 to one arm of a horizontally disposed rock-lever 2i! pivotally mounted intermediate its ends upon a fulcrumblock 2! suitably secured upon a vertically disposed presser-bar 22. rock-lever 20 is connected by a bent link 23 to a crank-arm 24 of a rock-shaft 25 journaled in bearing brackets at the rearward side of the bracket-arm 2. The rock-shaft 25 carries another crank-arm 26. connected to one end of a 20 posed by a spring 29, as more fully disclosed in 25 the prior U. S. patent of M. L. Waterman, No. 1,916,180, June 2'7, 1933.

The presser-bar 22 is mounted for vertical movement in bearing bushings 30 and 3| provided in the bracket-arm head 3, and is yieldingly depressed by a spring 32 in the usual manner. Secured upon the lower end of the presser-bar 22 is the shank 3t. of a presser-foot 35 having its tread portion. cut away at one side to provide clearance for the feeding foot Hi. The presser-foot 35 has an upturned toe portion 35' and a serrated work-engaging face having its heel terminating closely adjacent to a plane transverse to the line of feed and containing the needle at its limit of rearward or feeding movement. It will be understood from the foregoing description that the presser-foot 35 is vertically reciprocated to engage and release the work during each stitch-forming cycle and that the work is advanced by the feeding means while the presser-foot is raised above and clear of the work. The termination of the heel of the presser-foot closely adjacent to the needle-path, as above described, enables the presser-foot to step off from heavy cross-seams or other bulky Pivotally mounted upon the bed-plate l is the The upper end of the feed- 1 The other arm of the 15 usual attachment holder 36, upon which the base-plate 31 of the primary hem-forming guide or hemmer is secured, by screws 38, for adjustment of the hemmer crosswise of the line of seam formation. The base-plate 3! has an upstanding flange 39 to which is soldered or otherwise suitably secured a diminishing spiral hem-forming scroll, comprising an apron 40 merging into an upturned concave guiding wall 4| for initially forming the outer fold edge of a hem, said wall 4| continuing into a roof-portion 42 curving downwardly and inwardly as an inner fold-edge forming lip 43 extended axially of the scroll beyond said wall 4 Opposed to the inner fold-edge forming portion or lip 43 of the scroll, at the delivery-end of the hemmer, is an auxiliary upturned concave wall 44 for guiding the outer fold-edge of the hem, said auxiliary wall 44 being laterally yieldable to provide the necessary clearance when bulky ridges 000111 in the work passed through the hemmer. The auxiliary wall 44 is carried by one arm of an angle-lever 46 fulcrumed upon the base-plate 31 for horizontal swinging movements, by means of a pivot-screw 47. Connected to the other arm of said lever 46 is a spring 48 anchored to the base-plate to bias the wall 44 laterally into yielding engagement with the wall 4| to constitute a continuation of the delivery end of the latter. The base-plate 31 has an angular flange constituting a guide for directing the outer fold-edge of the formed hem, said flange presenting a guiding face 49 inclined to the line of seam formation and merging into a guiding face 50 substantially parallel to the line of scam formation. The guiding face 49 is inclined in a direction to deflect the outer foldedge of the formed hem into the plane of the face 50 and more particularly when the auxiliary wall 44 of the hemmer has been moved laterally by the work from normal position. The flange-face 50 is disposed adjacent to the presserfoot toe 35, said face 50 being preferably spaced at greater distance from the line of scam formation than the outer fold-edge guiding wall 4| of the hemmer.

The hemmer described serves to somewhat loosely roll the margin of a body material in the form of a complete hem, which becomes flattened as it passes under the presser-foot toe 35'. This flattening of the hem roll tends to widen the hem and it is to accommodate this effect that the guiding face 50 is spaced a greater distance from the seam line than the hemmer wall 4|. However, the laterally yielding movements of the wall 44 of the hemmer and also the hem-flattening action of the presser-foot make uncertain the final width of the hem to be secured by the stitches. To insure that the hem presented to the needle is of constant width, hem-shaping means is provided to act upon the hem between the delivery end of the hemmer and the needle.

To this end, a bracket 5| is suitably clamped upon the lower presser-bar bushing 3| and depends therefrom adjacent to the shank of the presser-foot. Fulcrumed between its ends upon said bracket 5|, by means of a pivot-bolt 52, is the carrier 53 of a hem-fold shaping member 54, a spring 55 being connected to the rearward arm of the carrier 53 and anchored to the bracket 5| to yieldingly urge the shaping member toward the work-support. The shaping member 54 has a vertically disposed edge-guiding face 54' extending substantially parallel to the line of seam formation and closely adjacent to the presserfoot 35, said shaping member being disposed at the side of the presser-foot opposite to the edgeguide flange 49, 56. The toe 56 of the shaping member is bent laterally away from the seam line and extends forwardly to a point adjacent the hemmer lip 43, whereby the delivery end of the hemmer is disposed between the shaping member and the edge-guide flange 49. Extending laterally from the lower edge of the shaping-member 54 and underneath the presser-foot toe 35' is a fin 51, of which the portion adjacent the toe 55 merges into a concave guiding face 58 of the shaping member, which guiding face is rear- Wardly inclined toward the line of seam formation. At its rearward end, the fin 51 is substantially normal to the face 54 of the shaping member.

As the hem rolled by the hemmer passes under the presser-foot toe 35' and is gradually fiattened thereby, the inclined concave face 58 of the I shaping member 54 acts upon the inner foldedge of the hem to crowd the inturned margin of the body material toward the outer fold-edge of the hem. The hem thus reshaped as it is flattened has its inner and outer fold-edges definitely located by the shaping member 54 and the opposed flange 59, undue thicknesses in the hem due to cross-seams and the like being accommodated by the vertically yielding movements of the presser-foot. Consequently, the width of the hem progressively presented to the needle is substantially constant.

Having thus set forth the nature of the invention, what I claim herein is:

1. In a sewing machine, stitch-forming mechanism including a reciprocatory needle, workfeeding means, a presser-foot, a hem-folder disposed in front of said needle having means for folding a margin of body material back upon itself to form the outer fold of a hem, and for inturning the edge of the folded back margin to thereby form the inner fold of the hem, a hemshaping member having a vertically concave guiding face inclined rearwardly toward the line of seam formation and disposed for engagement an outer hem-fold edge-guide opposed to said guiding face.

2. In a sewing machine, stitch-forming mechanism including a reciprocatory needle, workfeeding means, a presser-foot, a folder disposed in front of said needle having means for folding a margin of body material back upon itself and for inturning the edge of said margin to thereby form a helm-fold, hem-shaping means disposed between said folder and the needle comprising guiding walls arranged to narrow to a predetermined vvidth the hem-fold delivered by said folder, and means for reciprocating said presserfoot relatively to said hem-shaping means to engage and release the work during each stitchforming cycle.

3. In a sewing machine, stitch-forming mechanism including a reciprocatory needle, work' feeding means, a presser-foot, a hem-folder disposed in front of said needle having means for folding a margin of body material back upon itself to form the outer fold of a hem, and for inturning the edge of the folded back margin to thereby form the inner fold of the hem, opposed guiding walls for directing the inner and outer 1 fold-edges of said hem between the delivery end of said hem-folder and said needle, the inner foldedge guide being rearwardly inclined toward the line of seam-formation to thereby crowd the inner fold of the hem toward the outer fold thereof, and means for reciprocating said presser-foot relatively to said guiding walls to: engage and release the work during each stitch-forming cycle.

4. In a sewing machine, stitch-forming mechanism including a reciprocatory needle, workfeeding means, a presser-foot, a folder having means for folding a margin of body material back upon itself and for inturning the edge of said margin to thereby form a hem-fold, guides disposed at opposite sides of said presser-foot between the delivery end of said folder and said needle for directing the inner and outer foldedges of said hem, the inner fold-edge guide having a fin extending underneath said presser-foot, and means for reciprocating said presser-foot relatively to said guides. to engage and release the work during each stitch-forming cycle.

5. In a sewing machine, a Work-support, stitchforming mechanism including a reciprocatory needle, work-feeding means, a presser-foot, a folder disposed in front of said presser-foot having means for folding a margin of body material back upon itself and for inturning the edge of said margin to thereby form a hem-fold, guides disposed at opposite sides of said presser-foot and relatively arranged to narrow to a predetermined Width the hem-fold delivered by said folder, supporting means for the inner fold-edge guide providing for yielding movements thereof relatively to said work-support, and means for reciprocating said presser-foot relatively to said guides to engage and release the work during each stitch-forming cycle.

6. In a sewing machine, a work-support, stitchforming mechanism including a reciprocatory needle work-feeding means, a presser-foot, a folder disposed in front of said presser-foot having means for folding a margin of body material back upon itself to form the outer fold of a hem, and for inturning the edge of the folded back margin to thereby form the inner fold of the hem, a hem-shaping member disposed adjacent said presser-foot having a guiding face for the inner foldedge of the hem terminating in a fin extending underneath said p resser-foot, a fixed pivotal-support for said hem-shaping member, means yieldingly urging said member toward said work-support, and means for guiding the outer fold-edge of the hem delivered by said folder.

JAMES E. ACKERMAN. 

